JP4992878B2 - Traffic signal control system, signal control device - Google Patents

Description

  The present invention relates to a traffic signal control system that supports driving of an emergency vehicle.

  In the conventional traffic signal control system, for the purpose of supporting the travel of an emergency vehicle, an optical beacon is installed on the upstream side of the road connected to the intersection so that road-to-vehicle communication can be performed with the emergency vehicle. When the optical beacon receives the uplink information from the emergency vehicle, it recognizes that the emergency vehicle has approached the intersection and controls the signal lamp in the direction that the emergency vehicle passes. This is a traffic signal control method that continues to extend the green signal until it is finished, and if it is a red signal, switches the red signal to the blue signal as soon as possible and continues to extend the green signal, hereinafter referred to as “FAST control”). I came.

As a result, the emergency vehicle does not have to wait for the signal at the intersection, or the time for waiting for the signal can be shortened, so that the emergency vehicle can run smoothly. .
Since this FAST control operates differently from the normal operation of continuously displaying a green signal until an emergency vehicle can pass, there is a high probability that traffic congestion will occur in the traffic flow that intersects the direction in which the emergency vehicle passes. However, it is a traffic signal control method aiming at giving priority to the traveling in consideration of the social mission of the emergency vehicle even if the traffic flow on the crossing side is sacrificed to some extent (see Patent Document 1).

JP 2008-158837 A

  In this traffic signal control system that supports the travel of an emergency vehicle, when an emergency vehicle is traveling on a main road, FAST control is sequentially performed from the intersection at which the emergency vehicle approaches at a plurality of intersections adjacent to each other on the main line. Run it. When approaching a certain intersection, FAST control is performed at the intersection. After passing through the intersection, when approaching the next adjacent intersection, FAST control is performed at the next intersection. In this case, as a general rule, the FAST control is not started unless the emergency vehicle comes close to the downstream intersection farther away from the approaching intersection.

  As mentioned above, there is a demerit that traffic congestion tends to occur on the intersection side road when FAST control is executed, so it is uncertain whether an emergency vehicle will pass in consideration of the influence on the surrounding traffic flow In general, the FAST control is not executed at an intersection farther than the intersection where the emergency vehicle approaches. As described above, by limiting the execution target of the FAST control to only the intersection where the emergency vehicle approaches, the influence on the entire traffic flow in the emergency vehicle travel area can be limited.

However, if there is a traffic jam in the forward direction of the main road where the emergency vehicle is traveling, even if the traffic light at the intersection where the emergency vehicle is approaching continues to be green, it becomes a clogged state. Therefore, there are cases where emergency vehicles cannot move forward.
That is, there is a problem that there may be a case where the emergency vehicle cannot travel smoothly only by performing the FAST control at the intersection where the emergency vehicle approaches.
The present invention has been made in view of the above points, and an object of the present invention is to provide a traffic signal control system that assists an emergency vehicle to travel more smoothly.

A traffic signal control system according to the present invention includes a first traffic signal controller that performs traffic signal control at a first intersection, and a signal that transmits first command information that is an instruction to the first traffic signal controller. A control device and a first road communication device installed on a road connected to the first intersection, wherein the first road communication device receives uplink information from an emergency vehicle. For the first command information to be transmitted, FAST control is executed, which is a control method that continues to extend the green signal in the traveling direction of the emergency vehicle until it recognizes that the emergency vehicle has passed the first intersection. The signal control device further includes a second traffic installed at a second intersection where the emergency vehicle is expected to pass after passing the first intersection. No. said to the control unit is capable of transmitting a second command information to indicate different control method from the FAST control, the second instruction information transmitted in response to reception of the uplink information, the Information indicating that the display period of the green light in the direction in which the emergency vehicle is expected to travel is increased by a predetermined time from the normal display time determined according to the traffic demand is included (claim 1). .

  According to the present invention, in addition to the FAST control at the intersection where the emergency vehicle approaches, the display period (split) of the green signal in the traveling direction of the emergency vehicle is increased at the other intersection where the emergency vehicle is expected to travel. Therefore, it is difficult for traffic jams to occur where the emergency vehicle travels, and the number of cases where the emergency vehicle is prevented from proceeding due to clogging in spite of performing FAST control can be reduced. As a result, the execution effect of FAST control can be further enhanced, and the emergency vehicle can be strongly supported.

  Note that the traffic signal control device has a plurality of traffic signal controllers grouped into a plurality of subareas, and when there are a plurality of traffic signal controllers belonging to one subarea, these traffic signals In the case of instructing the system to operate systematically by giving an appropriate offset to the start time of the green light in a predetermined direction of the controller, the second traffic signal controller in response to the reception of the uplink information The third command information transmitted to the third traffic signal controller belonging to the same subarea as the one corresponding to the route in which the display time of the green light increases in the second traffic signal controller. It is desirable that information for instructing to increase the green light time of the road by the predetermined time is included (claim 2).

  When the green signal time is increased in the second traffic signal controller, the start time of the green signal of the second traffic signal controller in each cycle is delayed by that amount. If system control was performed by giving an appropriate offset in the sub-area to which the second traffic signal controller belongs, it belongs to the sub-area according to the increase in the green signal time of the second traffic signal controller. It is better to increase the green signal time of other traffic signal controllers so that the offset value is maintained appropriately. By doing so, system control in the sub-area is maintained, and smooth traffic flow in the sub-area is ensured.

Here, “the route corresponding to the route in which the display time of the green light increases in the second traffic signal controller” means the route in the traveling direction of the emergency vehicle at the intersection where the emergency vehicle is expected to pass. In an intersection where an emergency vehicle is expected not to pass, it usually indicates a route in the same direction as the traveling direction of the emergency vehicle. This is because when an appropriate offset is given to a plurality of traffic signal controllers in the same sub-area, when the green signal time of a route with one traffic signal controller is increased, another traffic signal controller This is because the offset in the sub-area cannot be maintained properly unless the green light of the route in the same direction as that route is increased.
Here, the green signal time to be increased in the third traffic signal controller may not be exactly the same time as the predetermined time to be increased in the second traffic signal controller. For example, if the time to increase in the second traffic signal controller is 20 seconds, the time to increase in the third traffic signal controller may be slightly different, such as 16 seconds (or 22 seconds), and operates. Any offset value given to the road R2 according to the cycle length or the like may be appropriate.

  In addition, the signal control apparatus used for the traffic signal control system of this invention is also very useful (Claim 3).

  As described above, according to the traffic signal control system and the signal control device of the present invention, it is possible to further enhance the execution effect of the FAST control and strongly support the traveling of the emergency vehicle.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic diagram showing an outline of a system configuration in a traffic signal control system according to the present invention.

[Overall system configuration]
As shown in FIG. 1, four intersections A to D are continuously arranged on the road R1.
At these four intersections, signal lamps are installed to display the right of traffic for vehicles traveling on the road R1 in the downward direction (the direction from the intersection A to the intersection D is referred to as the downward direction). Furthermore, traffic signal controllers 1A to 1D for controlling the signal lamp are installed.
Also, in the downward lane, optical beacons 2A to 2D are installed in order to perform road-to-vehicle communication with vehicles traveling in the downward direction, and upstream of the lane flowing into intersections A to D, respectively. Is arranged.

These traffic signal controllers 1A to 1D and optical beacons 2A to 2D can exchange information with the signal control device 5 installed in the traffic control center through a communication line or the like. The controllers 1 </ b> A to 1 </ b> D have a function of transmitting information related to the control history to the signal control device 5. In addition, the optical beacons 2A to 2D have a function of transmitting uplink information received from the vehicle by road-to-vehicle communication to the signal control device 5. The uplink information includes the vehicle ID of the vehicle, and the vehicle type of the vehicle can be determined based on the vehicle ID.
Note that the uplink information from the optical beacons 2A to 2D may not be received by the signal control device 5, but by an information providing device or the like (not shown) connected to the same network as the signal control device 5. There may be. In this case, the information providing apparatus or the like that has received the uplink information may transfer the uplink information to the signal control apparatus 5 or the like.

The signal control device 5 transmits signal control command information for controlling the signal lamp to each traffic signal controller, and the traffic signal controller that has received the signal control command information receives the signal control command information. Based on the above, the time distribution of the green light is determined, and each signal lamp color of the signal lamp is turned on.
Normally, this signal control command information includes an instruction for signal display for one cycle. Specifically, the cycle length of one cycle, the time of a blue signal assigned to each route, split, one cycle It includes an offset, which is a difference between the start time and the reference time, an instruction about whether or not to execute point sensitive control such as right turn sensitive control and dilemma sensitive control. The traffic signal controller that has received this signal control command information determines the signal control plan in the one cycle based on the latest signal control command information that has arrived at the time immediately before the start of one cycle, and the signal control Each signal lamp is controlled according to the display time of each signal lamp color included in the plan.

This cycle, split, etc. are usually determined according to the traffic conditions near each intersection. The traffic condition is measured by a plurality of vehicle detectors (not shown) installed on the road R1 and the like, and is determined based on sensor information (information including traffic volume and occupation time) collected by the signal control device 5. Is done.
For example, it is possible to grasp traffic demand such as saturation on each road based on the traffic volume (for example, traffic volume for 5 minutes) in a predetermined period and the average traveling speed, and length of the blue time allocated to each road intersecting with each other according to the traffic demand Determining etc.
One cycle refers to the period when the display of the traffic lights is completed. Normally, from the start of displaying the green light on the main road side, immediately before starting the display of the green signal on the main road side again. The period until.

Here, the signal control device 5 can create and transmit execution instruction information (information for notifying the approach of an emergency vehicle) that instructs each traffic signal controller to execute FAST control. When the traffic signal controller instructed to execute the FAST control receives the execution instruction information, it immediately shifts to the FAST control mode.
That is, if a green signal is displayed for the vehicle on the road R1, control is performed so that the maximum extension number of seconds (usually about 100 seconds) allowed to display the green signal can be extended. In addition, if a red signal is displayed for the vehicle on the road R1, the red signal must be displayed at least at the minimum guaranteed number of seconds (usually about 10 seconds) that must be displayed at least (already at least If the red signal is displayed for more than the guaranteed number of seconds, it is immediately interrupted), and the control is made so that the green signal can be extended to the maximum extension number of seconds.

When the signal control device 5 determines that the emergency vehicle P has passed the intersection, the signal control device 5 instructs the traffic signal controller that has ordered the execution of the FAST control to stop the FAST control. Stop instruction information (information for notifying the passage of an emergency vehicle) is transmitted. The traffic signal controller that has received the stop instruction information ends the FAST control mode and shifts to a normal control state.
For example, while the scheduled display time of the green signal that was scheduled before receiving the execution instruction information was 30 seconds, the display was continued for more than 30 seconds because of the transition to the FAST control mode. If there is, immediately stop displaying the green light. Further, if the stop instruction information is received in a state of less than 30 seconds after the start of displaying the blue signal, the green signal is continued for 30 seconds after the start of displaying the green signal according to the schedule before executing the FAST control. Just control.

[FAST control execution procedure]
In the traffic signal controller 1A of FIG. 1, FAST control is executed based on the uplink information from the optical beacon 2A located on the upstream side of the intersection. Then, after passing through the intersection A, the FAST control is stopped based on the uplink information from the optical beacon 2B. These procedures are described below.
First, the optical beacon 2A transmits to the signal control device 5 as soon as uplink information is received by road-to-vehicle communication.
The signal control device 5 has a configuration as shown in FIG. 4 and can always receive the uplink information through the communication interface 521. The received uplink information includes the reception time and the memory 511, the hard disk 512, and the like. It accumulates in the memory part.
In this case, a calculation unit such as the CPU 501 of the signal control device 5 refers to the vehicle ID information of the received uplink information and acquires information related to the vehicle type of the vehicle ID information. In addition, vehicle ID is comprised by the numerical value and the character string, and it is possible to identify the vehicle model of the vehicle based on the numerical value etc. which are included in the vehicle ID.

When the vehicle type of the acquired vehicle indicates an emergency vehicle, the emergency vehicle P is in emergency travel with reference to data included in the uplink information indicating whether the vehicle is in emergency travel. Get whether or not there is.
If the vehicle is in emergency travel, the signal control device 5 determines that the FAST control should be executed at the intersection A. In addition, when it is determined that FAST control should not be executed in consideration of conditions other than those described here (for example, time zone, traffic conditions, etc.), FAST control may not be executed. For example, when a time zone in which the FAST control is to be executed is set in the storage unit of the signal control device 5 in advance, the FAST control may not be executed in a time zone other than the time zone.

In this way, when the optical beacon 2A receives uplink information from the emergency vehicle P that is traveling urgently and determines that the traffic signal controller 1A should be instructed to perform FAST control, the signal control device 5 Then, execution instruction information for instructing execution of FAST control is created and transmitted to the traffic signal controller 1A.
As described above, the traffic signal controller 1A that has received this information can extend the green signal up to the maximum number of seconds if the green signal is displayed for the vehicle on the road R1 when the execution instruction information is received. On the other hand, if a red signal is displayed, the red signal can be extended to the maximum extended number of seconds after the red signal is cut off with the minimum guaranteed number of seconds and then switched to the blue signal. To control. Then, notification information indicating that execution of FAST control has been started is transmitted to the signal control device 5.

When the emergency vehicle P that is traveling urgently passes the intersection A, it now performs road-to-vehicle communication with the optical beacon 2B in the same manner as the optical beacon 2A, and transmits uplink information. Then, the optical beacon 2B immediately transmits the uplink information obtained from the emergency vehicle P to the signal control device 5.
When the traffic signal controller 1A receives the uplink information of the emergency vehicle P from the optical beacon 2B while the FAST control is being executed, the signal control device 5 determines that the emergency vehicle P has passed the intersection A. Then, stop instruction information for instructing the traffic signal controller 1A to stop the FAST control is transmitted.
As described above, when the traffic signal controller 1A receives the stop instruction information, the traffic signal controller 1A stops the FAST control and resumes the normal control.

In addition, since it is possible to determine that the emergency vehicle P that is traveling urgently has approached the intersection B by receiving the uplink information from the optical beacon 2B, the signal control device 5 this time FAST to the traffic signal controller 1B. Execution instruction information for instructing execution of control is transmitted.
In this way, FAST control is sequentially performed at the intersections A to D while the emergency vehicle P travels on the road R1 in the downward direction.

[Traffic signal control method at intersections beyond the FAST control execution intersection]
As described above, when the emergency vehicle P in emergency travel approaches the intersection A, the signal control device 5 transmits execution instruction information to the traffic signal controller 1A to execute FAST control. In the signal control system, instructions regarding traffic signal control are separately given to the traffic signal controllers 1B to 1D installed at the intersections B to D.

Specifically, signal control command information for instructing that the green signal in the downward direction of the road R1, which is the traveling direction of the emergency vehicle P, be made longer by a predetermined time (for example, 10 seconds) than the normal time. It is created and transmitted to the traffic signal controllers 1B to 1D.
For example, according to the traffic demand grasped from the sensor information collected from the vehicle sensor (not shown) installed in the vicinity of the intersection B or the like, the green time in the direction of the road R1 is temporarily 40 at the intersections B to D. If the blue time in the direction intersecting the road R1 is determined to be 30 seconds, the signal control device 5 sets the blue time in the direction of the road R1 to 50 seconds if FAST control is executed at the intersection A. The blue time in the direction intersecting the road R1 is changed to 20 seconds, signal control command information is created, and transmitted to the traffic signal controllers 1B to 1D. In this case, only the blue time in the direction of the road R1 may be increased to 50 seconds, and the blue time in the direction intersecting the road R1 may be kept at 30 seconds. The cycle length in this case is set longer by 10 seconds than in the normal case.

  In this way, it is expected that the emergency vehicle P travels in the downward direction of the road R1 at the intersections B to D that are farther than the intersection A that performs the FAST control and is likely to pass the emergency vehicle P. By instructing that the green light of (direction) be longer than usual, traffic congestion on the road in the direction in which the emergency vehicle P is expected to pass is less likely to occur. Alternatively, when a traffic jam has already occurred, control can be performed to eliminate the traffic jam.

In this case, a method of executing FAST control at the intersection B etc. at the same time as the intersection A can be considered. However, since it takes time until the emergency vehicle P finishes passing at the intersections B to D, it intersects with the road R1 at the intersections B to D. As a result, the red light is continuously displayed for a long time, and the possibility that the intersection road is congested becomes high.
However, according to the traffic signal control system of the present invention, it is only necessary to set the green time in the direction of the road R1 longer than usual, so that the traffic flow in the traveling direction of the emergency vehicle P is made smooth and the emergency vehicle P However, it is possible to limit the influence on the traffic flow of the road on the side that intersects the planned route of the emergency vehicle P to the necessary limit while reducing the probability of being blocked by the clogging.
In addition, when the emergency vehicle P makes a left turn at the intersection A, it becomes useless to change the signal control method for the intersection B or the like so that the emergency vehicle P is preferentially passed. In this case, it is advantageous in that the influence on the traffic flow of the intersection road at the intersection B or the like can be limited to a necessary limit.

Note that the predicted route of the emergency vehicle P may be stored in advance in the storage unit of the signal control device 5 or may be learned based on the routes of a plurality of emergency vehicles that have recently passed.
For example, if the uplink information from the emergency vehicle traveling in the direction of the road R1 of the emergency vehicle is received by the optical beacon 2A, the intersection where the FAST control should be executed is the intersection A, and the intersection that increases the green light is the intersection A pattern table indicating B to D may be stored in the signal control device 5 in advance. In this case, when uplink information is received from the emergency vehicle by the optical beacon 2A, the intersection where the FAST control is performed is the intersection A (traffic signal controller 1A), and the intersections which increase the green light are the intersections B, C and D (traffic It is only necessary to read out from the pattern table that the signal controllers 1B, 1C, and 1D) and create various instruction information and the like.

Further, for example, the track record of an emergency vehicle that has transmitted uplink information to the optical beacon 2A in the recent week may be stored, and the track record may be used.
For example, if an emergency vehicle receives uplink information in the order of optical beacons 2B, 2C, and 2D after passing through optical beacon 2A, the route of the emergency vehicle is a route that sequentially passes through intersections A to D. If there is, it is stored in the track record table.
Similarly, a method may be used in which track results of a plurality of emergency vehicles are stored in a track track table, and a route having a high frequency is determined as an expected track of the emergency vehicle.

In this case, two or more routes may be predicted instead of one, and the green light may be controlled to increase at all intersections existing on each predicted route.
For example, if the ratio of emergency vehicles turning left at intersection C and traveling on road R2 toward intersection E is not less than the ratio of traveling straight on intersection C toward intersection D, intersections B to D It is desirable to increase the blue time in the direction of the road R2 at the intersection E (the expected traveling direction when the emergency vehicle P passes the intersection E) simultaneously with the blue time in the direction of the road R1.

[Traffic signal control method considering subarea]
In the traffic signal control system, a plurality of traffic signal controllers to be controlled by the signal control device 5 are divided into several groups (the groups are referred to as subareas), and traffic signal control belonging to each subarea is performed. A traffic signal control method of transmitting signal control command information for instructing a machine to operate at the same cycle length may be used.
By operating at the same cycle length, as many vehicles as possible pass through all the intersections where these traffic signal controllers are installed during the time when the traffic signal controllers in the sub-area are displaying a green light. As a result, it is possible to perform system control that gives an appropriate offset to the signal display start time between the traffic signal controllers. FIG. 2 is a diagram showing the concept of system control.

In the present invention, it is preferable to control in consideration of the configuration of this sub-area.
In FIG. 1, for example, the FAST control is instructed to the traffic signal controller 1A in response to the emergency vehicle P approaching the intersection A, and the road R1 to the traffic signal controllers 1B to 1D at the intersections B to D. Consider a case where an increase in the direction green light time (eg, 10 seconds) is instructed.
The traffic signal controller 1E at the intersection E adjacent to the intersection C and the traffic signal controller 1F (not shown) installed at the adjacent intersection F are the same subarea as the traffic signal controller 1C, and the road R2 Assume that an appropriate offset is given to the display time of the direction green signal (see FIG. 2A). In this case, traffic signal control is performed so that the through band of the road R2 is secured by the offset given to the start time of the green light.

  When the green signal time of the traffic signal controller 1C is increased according to the present invention, as shown in FIG. 2 (b), the display time of the red signal displayed on the road R2 side of the traffic signal controller 1C is increased accordingly. End up. Therefore, the green signal start times of the intersections 1C, 1E, and 1F are different from the offset originally given on the road R2 side, which may cause a problem that the through band of the road R2 becomes narrow. When the through band is narrowed, the effect of facilitating traffic flow by dividing the sub-area into the system control is reduced.

Therefore, in the present invention, the green signal time is increased by a predetermined time at the intersection on the expected route of the emergency vehicle with the FAST control, and at the same time, the same traffic signal controller installed at the intersection on the predicted route. The traffic signal controller belonging to the sub-area may be controlled so that the green signal is increased by the predetermined time and the offset given in the system control becomes the same value as the original intention.
Specifically, as shown in FIG. 3, for example, the red signal time of the traffic signal controllers 1E and 1F in the direction of the road R2 (the green signal time on the side intersecting the road R2) is set as the road R2 direction of the traffic signal controller 1C. It can be increased as well. By doing so, the offset in the direction of the road R2 becomes an appropriate value, and the through band in the direction of the road R2 can be prevented from being narrowed.

  In addition, the signal control apparatus 5 and the traffic signal controller 1 etc. in this invention may be implement | achieved by one housing | casing, and may be implement | achieved by the combination of a some housing | casing. Each of these may be realized by one computer or may be realized by combining a plurality of computers.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a schematic diagram which shows the outline | summary of apparatus arrangement | positioning of the traffic signal control system which concerns on this invention. (A) And (b) is a figure explaining the outline | summary and subject of the system | strain control in the road R2. It is a figure which shows the mode of the system control in the road R2 of the traffic signal control system which concerns on this invention. 2 is a diagram illustrating an example of a configuration of a signal control device 5. FIG.

Explanation of symbols

1A to 1D Traffic signal controller 2A to 2D Optical beacon 5 Signal control device

Claims (3)

A first traffic signal controller for performing traffic signal control at the first intersection;
A signal control device for transmitting first command information which is an instruction to the first traffic signal controller;
A first road communication device installed on a road connected to the first intersection,
In the first command information transmitted in response to the first road communication device receiving uplink information from the emergency vehicle, the emergency vehicle indicates a blue signal of the traveling direction of the emergency vehicle. In the traffic signal control system including information instructing to execute FAST control, which is a control method that continues to be extended until it is recognized that the vehicle has passed the intersection,
The signal control device further includes:
Second command information for instructing a control method different from the FAST control to a second traffic signal controller installed at a second intersection where the emergency vehicle is expected to pass after passing the first intersection Can be sent,
The second command information transmitted in response to the reception of the uplink information includes a normal display time in which a green signal display period in a direction in which the emergency vehicle is expected to travel is determined according to traffic demand. The traffic signal control system further includes information instructing to increase the time by a predetermined time. The signal control device includes:
When a plurality of traffic signal controllers to be controlled are grouped into a plurality of sub-areas, when there are a plurality of traffic signal controllers belonging to one sub-area, a predetermined direction of these traffic signal controllers To give an appropriate offset to the start time of the green light and direct it to work systematically,
The third command information transmitted to the third traffic signal controller belonging to the same subarea as the second traffic signal controller in response to the reception of the uplink information includes the second traffic signal. 2. The traffic signal control according to claim 1, further comprising information for instructing to increase a green signal time of a route corresponding to a route in which a display time of the green signal is increased in the signal controller by the predetermined time. system.   The signal control apparatus used for the traffic signal control system as described in any one of Claim 1 or 2.

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